Boston's 2021 population is now estimated at 4,314,893. In 1950, the population of Boston was 2,550,818. Boston has grown by 6,259 since 2015, which represents a 0.15% annual change. These population estimates and projections come from the latest revision of the UN World Urbanization Prospects. These estimates represent the Urban agglomeration of Boston, which typically includes Boston's population in addition to adjacent suburban areas.